Improvement in steam-engines



tnt mes pero entre Letters' Patent` No. 93,414, dated August 10, 1869; a-'ntedated August 3,1869.

IMPRQ'V'EMENT IN STEAM-ENGINES.

To all whom it 'mo/y concern:

Be it known that I, WILLIAM O. CHAMPLIN, of Allegheny City, in the county of Allegheny, and State of Pennsylvania, have invented a new and useful Improvement in Steam-Engines j and I do hereby declare the following to be a full, clear, and exact descn'ption thereof, reference being had to the accompanying drawings, in two sheets, making a part of this specification, in which- Figurel shows in perspective a steam-cylinder fitted with my improvements; v

Figui-e2 is a sectional elevation, as lookedat from the rear or further side of fig. 1, the section being formed by a plane passing vertically and longitudinally along between the cam or driving-shafts and the steam-cylind er Figure 3 shows, in a detached view, in perspective,

` the adjustable devices of figs. 1' and 2, by which I regulate the point of cut-off; and 4 Figuresl 4 and' 5 are detached views, as presently to be explained.

Like letters 0f reference indicate, in the diderent figures, like parts.

` The -natureof my invention consists in the construction o f an improved adjustable cut-off for steamengines, such, that by its use the apparatus for opening the valves may be so adjustedv at any time, and with a moments work, and without stopping the engine, as to open and close the valves andtake and cut of steam at any desirable point of the stroke; and

Itvfurtheryconsists in the use otsuch adjustabledevices in connection with a governor, as a means of regulating the supply of steam to the cylinder. A To enable others skilled in the art to make and use my invention, I will proceed -to describe its construction and mode of operation.

A is a steam-cylinder, of' the usual or any known l construction, and is fitted with a piston operating a piston-rod, B.

Into the cylirxder A, at each end, .steam is admit- .ted through poppet-valves in the valve-chests a, the

valves being'operated by the valve-stems a' connected therewith.

In the drawings a a represent the steam-valve chests, and l) b, the exhaust-valve chests. l The usual ports lead from and to the steaml and exhaust-pipes C and C'.

'I he -Schedule referred to in these Letters Patent and making part ot the same.v Howmotion, and both being hung on the same axle or shaft, d.

From the lower face of the outer end of each lifter,

`c,is hung, so as to swing freely within certain limits,

a pawl, c", as shown in figs. 2 and 3. On the same shaft, d, but outside` the wipers or lifters c, is fixed a sleeve, d', which carries and operates a circular or segmental head, d, directly under the lifters c and pawls c'.

On the saine axle, d, but inside the wipers or lifters c, .I place, so as to work freely thereon, a frame, c, of' the form shown in g. 4.

The upper end of this frame has a projection, c', on its inner side, through which I Work a threaded screw, e", and to the lowerend of the screw,by a swivel-joint, attach a sliding guide, fi, with itsv face against the frame c.

This sliding guide is slotted where the shaft all passes through it, so as to be adjustable up and down by the screw e, as presently to be described.

In its lower part, ithas three slots, sys s, which converge towardtheir upper ends, as shown in fig. 3.

The frame c, which plays on the shaft d, just inside the wipers c, has a circular or segmental groove or notch in-each edge of its lower part, as shown in Y fig. 4

headed bolts s passing through the outer slots s, each enter one ofthe sliding blocks o.

Then, as the sliding guide f1, is raised or lowered by the screw c, the bolts-s', operating in the slotss,

are made to `approach to or recede from each other. As the sliding guidei is lowered, they are brought nearer together, and thereby the sliding blocks o are caused to enter the frame c, and 'vice fvcrsa.

These blocks o are virtually the arc of a circle, and by sliding them out of or into the notches in the frame c, I lengthen or shorten the arc. 4

A plan or upper face view of these blocks is given inl iig. 5. v L

The .parts which work in the notches are marked o. On the rear edgejof each of these, and forming in each a part thereof, is a wing, o','which, 'when the block o is in place,J as in figs. 1,2, 3, and 4, so pro-v n each groove ornotch plays a segmental sliding jects as to come directly under the liftcrs c, already described, and a little above the segmental head d, and of course, then, in a plane with both.

In the outer or working ends of the wings o', frictionrollers, lr, .are inserted, and like rollers, i", in the outer ends of the segmental head el.

Between each pair of friction-rollers, r r, the lower end of one of the pawls, c', operates.

It will now be observed that as the blocks o are run out, as already described, the wings o' will also recede 'from each other, and the distance lbetween their working ends, or between the rollers fr vibe increased, and rice terse.

It will also be observed that the levers D, lifters e, palwls o', wings o', and segmental head d, all stand in the same vertical plane.

Each pawl, o', is brought to ar point, or,.in other words, its lower rnd is bevelled on either face, so as to roll easilyoa the diction-rollers r lr', against which it operates. v

A stop, 11, projects downward ti'om the outer end of each lifter, c, so as to prevent its pawi, c', from passing outside of-or below the segmental head d.

Its own weight prevents it from going inside` or above the wing o', and the segmental head d" and wings o are adjusted so close together that the pawls e cannot slide down between them. Consequently, each pawl, c', must work above the segmental head d, the wing o' being withdrawn, or below the wing o', the head d" being withdrawn, or be carried upward by the joint action of the two.

Parallel to the shaft d a similar shaft, f, on which is a crank, f', which is connected by an arm, g, with the upper end of the trame e, which last, it will be remembered, operates freely on its shaft d.

Each of these shafts, d f, receives a motion independent of the other, by conneoting-rods, E E; the cams or eccentries which operate them being `so set that` one shall move a little in advance of theother.

It will be obvious, then, that the segmental bead, 11", receiving its Iuotion through the shaft (l, with which it is connected, will have a motion independent ofthe wings o', which receive their motion from the other shaft f, through the frame e. Consequently, while the head df is moving by an oscillating motion in either direction, the wings o' may, through apart of their stroke, according to how much one eccentric shaft, E', operates in advance of the other, E, move in directly the opposite direction; or, while one is moving one way, through a partofthe stroke,the other maybe stationary.

At the dead-points, each pawl, c', rests with its point orA lower end against the friction-rollers r r of the head d" and the corresponding wing o.

The devices described are so adjusted that the shaft f shall work a little in advance of the shaft d, and consequently, thc wings o' make their stroke a little in advance ofthe head df; but the head d" soon follows, and the valve is opened by the joint action of the two, that is, they raise the pawl c', liftersc, and lever l).

The shafts dfhavc a rockingmotion.

At the point of cut-off, the wings o commence their return stroke first, the pawl c' following down inside the head ll, which remains stationary, or nearly so, and the opposite wing going up inside of its pawl. Consequently, the former of the litters c comes down, closes its valve, and cuts ofi' steam, while the opposite lifteris not raised nor its valve opened until a little later, Vwhen the head d, actuated by its later-moving shaft d, commences its revturn stroke. Then, the head d", acting in conjunction with the opposite wing o', already in advance, raises the. opposite pawl, c', lifter c, and lever D, and the opposite valve is opened, steam is admitted,rand so on, alternately.

But to make the cut-0d' adjustable, I use the screw and frame t already'described.

By raising the sliding frame z', I cause the bolts s', working in the inclined slots s, to recede from each other. Thereby, the sliding blocks o are driven outward, and the wings e attached thereto, of course recede from cach other, and the distance from end to end of the wings o'v becomes more nearly equal to the length of the head d".

By lowering the frame exactly the opposite result'is secured, that is, thedistanee between thev opposite ends of the wings o is lessened.

In either case, the valve is closed, and steam is cut oft' by either pawl, c', following its wing o downward. Consequently, the less the distance between the opposite ends of the wings o' o', the sooner the pawl will reach the end ot' its downward stroke, the valve be closed, and steam be cut o, and cioe versa, so that by lengthening or shortening the are formed by the wings o' o', I change the point of cut-od, making it earlier or later in the stroke of thev piston.

And this lengthening or shortening of the arc, it will be remembered, is effected by the, screw e". n

This result is further facilitated by the fact that when the wings are farthest distant from each other, and, ofcourse, the are formed thereby is the longest, their working ends, at the highest points of their :stl-oke, risc higher than the working ends of the head d". Then, when the wings commence their reverse stroke, they have to more till the working end uppermost has passed the working end ot' the head d",

before the pawlv begins to come down and cut off steam.

Hence, the wings o' in such case have to move through a part of their stroke before cutting olf begins.

As these wings are brought together, and the are formed thereby is shortened, the length of that part of the stroke which it makes before the cut-off begins is lessened, until each wing, at the end of its outward stroke, moves no further than the corresponding end ofthe head d.

Then, as soon as either wing begins its return stroke, its pawl will begin -to fall, the lifter c and lever D will follow, the valve begin to close, and steam be cut off.

And to vary this point of cut-oil', nothing is required except turning the` screw c, so as to move the sliding blocks o toward or away from each other.

In the front of tig. 1 are shown the devices for operating the exhaust-valves,

b'b being the valve-chests.

F F are levers;

h. h are valve stems; and

n` n are lifters.

The shaft d, by a crank-connection, my, operates t-he shaft m', which, though in line with the shaft j', yet is not a part of it.

Another crank-connection of similar character, but not shown, then communicates. motion to the lifters ny n..

By these the exhaust-valves are opened and closed alternately with the others, but, of course, at the commencement of each stroke of the piston.

To reverse the motion ot' the. engine, the connecting-rod E'may be unhooked from its crank and attachcd to an opposite crankfwrist on the same axle.

l also, whenever desirable, substitute, in my invention, a steam-governor for the screw e, and by its action raise or lower thc sliding frame or guide, and so adjustsuch governor thereto that if the'powcr be 'too great, the engine will cut oii earlier in the stroke,

variable l:self-operating cutfoii', and make it perform many or all of the functions of a governor'at the throttle-valve; and such use I include in my invention. i

Having described my invention,

What I claim therein, and'desire to secure by- Letters Patent, is-

1. The adjustable cut-oli', in which the pawl c', at

`the 'end of each lifter, c, shall operate against .the

ends of the segmental head d" land wing o', thev latter being-adjustable, andA all arranged substantially as set forth. Y

2. The frame e, .mortised or slotted to receive the sliding blocks'o, and hung on the shaft d, and connected to an independently-'operating shaft, ar

ranged substantially as hereinbefore set forth.

3. The sliding guide fi, with inclined slots s, andV the bolts s', for adjusting the wings o' through the blocks o, and furnished with a screw, e, all constructed and arranged substantially in the mannerl above set orth.

In testimony whereof, I, the said WILLIAM C.

GHAMPLIN, have 'hereunto set my hand.

WM. o. CHAMPLIN.

` Witnesses:

J. W, KIRKER, G. A. SHALLENBERGER. 

